The Customer user ID is a free text field that contains a key identifier of your user used to cross-reference recorded installs by AppsFlyer. The field is a free text field that contains data in a format that suits you. The data is available in the raw data reports in the Customer user ID column.
How does it work?
The SDK provides a function allowing you to populate the Customer User ID in the dedicated field. Refer to the Set Customer User ID section of the SDK Integration Guides (iOS, Android, Unity) for more details.
Once the Customer User ID is set, each and every event recorded by AppsFlyer contains this ID. This allows you to cross-reference AppsFlyer data with your data, using the Customer User ID as key.
For example, one user with two devices can have the same Customer User ID. Each time they perform an event on either device, it is recorded under the same Customer User ID. Allowing you to clearly understand the true value of the user over both devices.
- It is highly recommended to set your Customer User ID as soon as possible, since it is only associated to events reported once the attribute has been set. Ideally it should be placed before the
startTrackingmethod API call to have the Customer User ID as part of the raw installation data.
- If you choose to work with integrated data partners such as Mixpanel or Swrve, you are required to set the Customer User ID for the integration to work effectively.
Customer user ID for people-based attribution
AppsFlyer's people-based attribution (in beta) gives you a wider perspective on the impact of web and mobile campaigns, as well as the ability to analyze your efforts to switch web users to your mobile app and vice versa. If you are using AppsFlyer's people-based attribution (PBA), it's important that you set the same customer user ID in both mobile and web, to enable cross-platform insights and analytics.
Delay SDK init for customeruserid
You can delay the SDK Initialization until the customerUserID is set. This feature makes sure that the SDK doesn't begin functioning until the customerUserID is provided. If this API is used, all in-app events and any other SDK API calls are discarded until the customerUserID is provided.
The upside of this API is that data in AppsFlyer is always associated with a customer user ID. When you pull the data from AppsFlyer to your own BI systems, you always know which user to associate data with. This helps you perform a more accurate analysis of the data that you get from AppsFlyer.
The downside of this API is that actions and events that users perform, purchase and subscriptions among them, don't show in your dashboard and are practically lost to you.
Use this feature only when it matches your business logic. Using this API increases the chance for discrepancies and might make the app more exposed to fraud.
To learn how to use this API, click here.